Sewing machine



Nov. 3, 1953 c. L. KNOTT' 2,657,653

SEWING MACHINE Filed Feb. 10, 1950 11 Sheets-Sheet 1 Inventor Clyde L. [620% By his j??? "C. L. KNOTT SEWING museums Nov. 3, 1953 2,65 7,653

11 Sheets-Sheet 3 Filed Feb. 10, 1950 Inventor Clyde L. Knott By his Aftorrz y Nov. 3, 1953 g. KNOTT 2,657,653

SEWING MACHINE Filed Feb. 10, 1950 11 Sheets-Sheet 4 Inventor Clyde L. Knotz, By his Attorney Nov. 3, 1953 c. KNOTT 2,657.653

. SEWING MACHINE Filed Feb. 10. 1950 11 Sheets-Sheet 5 Inventvr Clyde L. Knott By his Attorney Nov; 3, 1953 c; KNOTT 2,657,653

SEWING MACHINE Filed Feb. 10, 1950 11' Sheets-Sheet s a inventor Clyde L. Knozz By his Attorney Nov. 3, 1953 c. L. KNOTT 3 SEWING MACHINE Filed Feb. 10, 1950 ll Sheets-Sheet 7 6 my 5 Ill. [95 a4 \1 250 212 250 @jJZlZ Inventor Clyde L. Knot?) By his Atlf orney Nov. 3, 1953 c. L. KNOTT 2,657,653-

SEWING MACHINE Filed Feb. 10, 1950 11 Sheets-Sheet 8 Inventor Cllyde L. Knott By his Attorney Nov. 3, 1953 c. L. KNOTT 2,657,653

SEWING MACHINE Filed Feb. 10, 1950 11 Sheets-Sheet 9 Inventor Clyde L. [020% By his Attorney Nov. 3, 1953 c. L; KNOTT 2,657,653

1 SEWING MACHINE Filed Feb. 10, 1950 11' sheets-sheet 10 Clyde L. Knott 5% ins Attorney Nov. 3, 1953 c. KNOTT' 2,657,553

SEWING MACHINE Filed Feb. 10, 1950 ll Sheets-Sheet 11 AWL NEEDLE TAKE-UP FEED FREE OF WOR THREAD LOCK inventor Clyde L. Knozft By his Attorney Patented Nov. 3, 1953 SEWING MACHINE Clyde L. Knott, Beverly, Mass., assignor to United Shoe Machinery Corporation,

Flemington,

N. J., a' corporation of New Jersey 39 Claims. 1

The present invention relates to machines for sewing shoes or other articles composed of stifi heavy materials with a lock stitch seam, and more particularly to improvements in the type of machine employing a straight hook needle to enable speeds of operation higher than obtainable with previous similar machines. In certain aspects, the invention is of more general application to machines including that type employing curved needles, whether intended for inserting a lock or a chain stitch seam.

Shoe sewing machines of the hook needle type ordinarily are somewhat more heavily constructed than those of the eye-needle type and, consequently, the actuating devices of such machines have greater inertia and cannot be operated efficiently at relatively high sewing speeds. For this reason, and because shoes or other parts intend to be operated upon are composed of heavier materials than those operated upon by machines of the eye needle type, no attempt has been made heretofore to construct a hook needle machine intended for operation at speeds greater than a thousand sewing cycles per minute. Ordinarily practical speeds for hook needle machine operation are far below this figure.

It is an object of the present invention to provide a hook needle shoe sewing machine of improved construction and advantageous mode of operation in which relatively heavy parts are employed, as compared with the parts of an eye needle sewing machine, but which is capable of practical operation at speeds inexcess of "a thousand stitch forming cycles per minutewithout the difficulties encountered in high speed operation of similar prior machines. A furtherobject of the invention is to provide a sewinglmachine of the type referred to which will have greater durability, a higher quality of work performance and a smaller requirement for skill or effort on the part of the operator of the machine.

One difficulty frequently encountered in the operation of any high speed shoe sewing machine is in imparting a uniform feeding movement to the work operated upon without exerting on'the work such heavy clamping pressure as to injure the surface or to flatten the work to a degree where permanent distortion occurs. 'According- 1y, one feature of the invention resides -in the use of a relatively stationary guide foot against which the work is held, and in a worksupport movable toward the guide foot to clamp the work, a feed foot being connected to the work support by a floating actuating lever to cause thework support to be, lowered positively from.

' i g 1; I Application February 10, 1950, Serial No. 143,536

2 engagement with the work during the feeding movement of the feed foot. This arrangement differs from the usual one in which the work support comprises a fixed clamping member and the feed foot only moves to clamp the work. The work is held in the usual machine against the work support at all times and isguided by engagement therewith. During normal operation of such prior machine, the tendency is to force the work so firmly'against the work support that freedom for full unrestricted feeding movement of the work is substantially impaired. Accordingly, variation in stitch length results. By the use of a feed foot actuated through a floating lever connected to the work support, the work support is disengaged from the work during feeding movement by the resistance offered to the clamping pressure of the feed foot. Consequently, the grip of the feed foot on the work may be made much lighter than in a machine having a fixed work support. Preferably, a pair of feed feet is employed, acting at both sides of the work, both feet being actuated simultaneously to clamp and feed the work.

Another feature, of the invention which enables higher sewing speeds, particularly in the use, of a hook needle and. an awl, is that embodied in a rotary needle looper arranged with its axis in alinement with the awl and provided with an awl guiding opening into which the needle enters during the looping operation. This feature consists in providing a, thread measuring finger mounted for rotation about an axis at an angle to the rotating axis of the looper. In one form of this feature a member cooperates with the thread finger to insure that a uniform length of thread will be measured. As hereinafter illustrated, the thread finger is provided with an arcuate thread engaging flange and a concave member within the concavity of which the thread finger traps thread between the concave member and itself during the thread measuring operation.

Otherfeatures including a novel and improved loop picker assist in transferring each loop of thread from the needle to the shuttle, and as hereinafter described and claimed will be apparent from the following detailed description and accompanying drawings, in which l is a V ew n rightv side elevation of a m h embodying the features of the present invention; I

Fig. 2 isa front view on an enlarged scale of the machine illustrated in Fig. 1; I

of rotating varying speed-ratio drives, one or which is employed for the feed foot and the, other for the awl actuating mechanism;

Fig. 6 is a detail view partly broken away and in section of the needle, awl and loop picker fac tuating mechanisms of the machine illustrating the positions of the parts at. the. end. 02 the. penetrating stroke of the awl;

Fig. 7 is a similar view of the parts at the end of the work penetrating stroke of the needle;

Fig. 8 is a detail view in. front. elevation on, an enlarged scale showing the. relationship of the needle, awl, looper, loop picker and shuttle. while the machine is in stopped position or at. the beginning of a sewing cycle;

Fig. 9. is a similarview of the. same parts taken during the. penetrating stroke of the awl'fand corresponding to. the. position of parts shown: in

10-is a similar view of; the parts takenduringthework penetrating stroke of the needle 11 is a. similar View of the parts showing the loopingoperation of the needle;

Fig; 12; shows the position of the parts while the threaded needle is retracting from the work;

13 is-a similar View of the. same parts show. ing! the operation. of the looppicker. in. transferrin'g a loop. of threadfrom the needle to the shuttle;

Fig. 1 4 is a front view/ofthe same. parts showing a needle loop beingdisengaged" fromv the shuttle;

' Fig. 15 is a view infront elevation of the take up actuating mechanism in a position taken at the beginning of a sewing cycle;

Eig. Leis a similar view-of thesame-meohanism showing the take up atthe limit of its thread giving-upmox ement;

Fig. i 71 is av detail view in frontelevation of v the thread measuring finger. and; its actuating mechanism taken at. a time; in. the operation of the machinecorre'spondingtothat. illustrated Fig 9 Fig;,118ti$.fi similar View of thesamespartsitaken durin e. oopin peration f-.-the needle as lustrated n. Eia .1;

We a de il an. of th ooser" ac.- tuating mechanism correspondingv to: the positiq soi herarts; shown. n Fig. .0;,

E e-. .0 i. .a im lar view of the same pa t aken in t are: the. oop n p rati n has. been compigtails,

' Fig. 21 is a View in front elevation of the parts as shown in Fig 19;

' Fig. 22 is a similar view of the parts asyshown in Fig.

Fig. 23 is a detail; view in front elevation of-th'e thread lock time adjusting connections" and a part ofthe actuating mechanism therefor;

Fig. 24 isa similarvie winrightside elevation of some ofthe connections and mechanism illustre-ted in Fig. 23* but displaced in relation to each other from that assumed during" normaloperation;

Fig. 25 is a time chart of certain parts inc-111ding the principal stitch forming devices and feed feet in the machine; and

Fig. 26 is a perspective view on a somewhat reduced scale of the thread finger actuating mechanism.

The illustrated machine is a lock stitch shoe sewing machine intended for operation upon relatively heavy stiff materials including sole members to insert a seam at speeds higher than employed in present day practice for corresponding machines. The illustrated machine is capable of operation at approximately 1500 stitches per minute as compared with 700 to 800 stitches per minute maximum for similar machines in present principal actuating mechanis s for the stitch forming. and work feeding d vices are camless 3 day usage. In the attainment ozfghis speed all the and are driven through are k, and pitman connectionswith the main sewing shaft to assist in obtaining the proper tifrning of the stitch forming and other'actuate devices. Rotating varyins: speed=ratio driv s are employed with certain of: the mecha sms. to.- insure'smooth operation.

Referring more; particularly to the, drawings, the stitch. forming devicesof the machine include a work penetrating straight: hook needle 2 operating; below the work,- a. work, penetrating straight owl 4; atjthe opposite side ofi: the: work, a, shnttleor loop taker i atthe same side-of; the work; with the needle. a. rotaryneedle looper 8, a thread measuring; finger I10: acting on.the', ne.edle thread stretched. between the. needle: looiper' and the Work a poinfiediloop picker t2, a taker-upit, andaeombinedithrcad tensionandlock 1-6;. The formation of a seam, by; thestitch formingdevices is; generally similar to: that. prior; ma.- chines... the being. clampedduring stitch formation betwfi nastationary guidefoojt liBland a. yieldingly actuated work support. 20:.

It. isgthei usnal'ipractice; in the. design of. straight needle sewing machines. particularly thosetended for; operation on stifii'heavy materials; to preside; a, stationary work support and to.- enable theworkrtobe clamped mfixed position by move-- ment toward and from the Work support of a movable pn'esser foot. In presenting; thework to the machineand in changing its: position asthe operation. progresses. the: operator presses the work: downwardly againsttheiwork support: causing a frictional dt'ag. to. be; exerted on. the work by theiworln support and imposinganobstacle to .uniforrmiceding action of the. machine.

In. the: machine; of the; present invention, the frictional drag of the. work on the; work support during feeding movement is in. large degree overcome, the, work support being raised yi'eldingly against. the work andbeing moved: positively downwardly: away. from. the; work during each feeding movement. and the work being maintained: in. suspension momentarily during feed between the, worksupport and guide foot 18. To. impart: downward movement of theworksupport awayfrom-..-th-e workduringwork feed, the work supportv has. connected to; it a feed foot 22, through a.flo'atinga actuating:leyer 24 of elbow form (seetFi'gr 5). Therfloatingle'ver is ful crumed: on a stub shaft 1H mounted in "the work support. To counteract the upward pressure of the'feed foot and to stabilize theposition of the work in suspension between the work support and guide foot, there is provided asecondfe'ed foot 26- at the upper side of the work acting in a similarmanner but an opposite direction dis? engaging the work from the guidefoot. Thus.

the weight of the work and the downward pres sure exerted on the work by the operator cause no undesirable frictional drag on the work support and as a result a lighter clamping action of the pair of feed feet 22,26 can be used than otherwise would be necessary.

The work support is movable toward and from the guide foot by reason of its mounting in a vertical guideway 28 (see Figs. 2 and 5), formed by a pair of parallel grooved plates 39, secured to the outside surface at the forward part of a hollow enclosing frame 32 by machine-screws 34. The side edges of the work support are formed with parallel ferrules 39, entering the grooves of the plates 39. The work support is inv the form of a shell with a tapering upper work engaging end perforated and slotted to receive the needle and the feed foot 22.

To raise the work support yieldingly and maintain it in clamping engagement with the work against the thrust of the awl, the work support has surrounding a sleeve portion 31 thereon the upper end of a link 39, the. lower end of which is pivotally connected to an arm 49 secured to a shaft 42 rotatably mounted inthe machine frame 32. The shaft 42 extends rearwardly of the machine and has fixed to its rearward end a vertical arm 44 (see Fig. 4) pivotally connected to a bar 46. The bar 46 has a shoulder engaged by a coil compression spring 48, and is slidingly mounted in a tubular bushing 59 threaded in the right side wall of the machine frame. The inner end of the bushing acts against the spring 48 to enable the compression of the spring to be varied and the upward pressure of the work support on the work to be increased or decreased. To limit the upward movement of the work support when no work is presented to the machine, the vertical arm 44 engages a stop pin 52 projecting inwardly from the machine frame.

Referring further and more particularly to Fig. 5, the upper feed foot 26 is pivotally mounted at 54 on an elbow actuating lever 56. The lever 56 is fulcrumed on a stub shaft 58 secured in the frame 32 of the machine.

In feeding the work the feed feet 22, 26 engage and clamp the work at the forward side of the seam line and move from right to left a stitch length while in engagement with the work. To this end the elbow levers 24, 56 for actuating the feed feet against the work are given equal rocking movements about their respective fulcrum shafts and 58.

The mechanisms for actuating the elbow levers to clamp and release the work are similar to each other and are connected for vertical sliding movement to the longer arms of the levers. These mechanisms comprise diametrically slotted pins 69 and 62 surrounding at their slotted ends the reduced ends of the levers, the pins being rotatably mounted in arms 64 and 66, respectively, secured to the forward ends of a pair of horizontal shafts 68 and I9. The shafts 68 and 19 are rotatably mounted in the machine frame and have their rearward ends fixed to arms I2 and 14 extending relatively in opposite directions from their respective shafts. The free ends of the arms I2 and I4 are connected to a pair of pitmans I6 and I8 engaging separate cranks 89 and 82 of equal throw disposed 180 apart on a shaft 84 comprising the main sewing shaft of the machine. The arrangement is such that in clamping the work the pressure exerted by the feed foot 22 causesthe work support 29 to be forced downwar y i it way .28 and .mQYln @W 2 6. wardly the lower-end of the elbow lever 24 slides vertically in the slot of the pin 69 without disturbingthe movements of the parts. I

To impart feeding movements to the feed feet 22, 26 the lower end of the feed foot 22 and the upper end of the feed foot 26 are connected by horizontal links 86 and 88 to upwardly projecting arms 99 and 92, respectively secured to the forward ends of a pair of horizontal shafts 94 and 96. The shafts 94 and 96 have secured to their respective rearward ends a pair of arms 98 and I99 connected in turn through a pair of links I92 and I94 to opposite ends of a single vertical lever I96 rotatable at a central point along its length on a fixed shaft I98. The shaft 96 is rotatable in fixed bearings and the shaft 94 is rotatably mounted in a bearing carried by the work support. The bearing for the shaft 94 comprises the sleeve portion 31 of the work support 29 and moves vertically with the work support. However, the horizontal link I92 swings slightly during vertical movement of the shaft 94 without affecting its angular position. The hub of the arm 98 abuts the link 38 and holds it from axial displacement from the sleeve portion'3I of the work support 29, as best shown in Fig. 3.

Since the ends of the vertical lever I96 move in opposite directions a motion reversing connection is necessary between the connecting lever and one of the feed feet. In order to cause the feed feet to move along the line of feed in the same direction, the arm 92 projects upwardly from the shaft 96 and the arm I99 projects downwardly, and the arms 99 and 98 on the shaft 94 for the lower feed foot both project upwardly. Thus, the arm 92 moves in the same direction as the arm 99 and reverses the motion produced by the ends of the vertical actuating lever I96.

To provide convenient means for varying the feeding movements of the feed feet, an adjustable throw connection is included in the feed foot actuating mechanisms. The adjustable throw con,- nection comprises a pair of toggle links II9' and II2 pivotally connected between the lower end of the vertical lever I96 and a forked arm I I4 56- cured to an adjusting shaft H6 rotatable in the machine frame. The adjusting shaft H6 also has fastened to it a gear segment H8 meshing with a worm I29 integral with a shaft I22. The shaft I22 is rotatable in a flanged bearing I24 (seeFigs. l and 2) fastened to the right side wall of the machine frame 32, the worm I29 being disposed inside the frame. Outside the frame the shaft I22 has pinned to it av crank arm I29 (Figs.- 1 and 2) within the crank portion of which is slidingly mounted aspring pressed plunger I23 arranged to engage at its inner end selectively with one of a'series of holes I39 in the flange of the bearing I24. Rotation of the crank through the connection described, changes the position of one end of the toggle links.

The central joint of the toggle links consists of a pin I32 at the outer ends of which is a pair of connecting links I34 (see Figs. 3 and 5). The

yoke I36 through a pair of pins I38. The yoke I36 has fulcrum 'studs I49 projecting outwardly therefrom and rotating in bearings in the machine frame.

The yoke I36 is actuated to move the links I34 and the central joint pin I32 of the tog le links l ei s e e e l res nters as mant e;

links I34 connect the pin I32 with the arms of a 7 connected to a pitman I42 driven by a crank I projecting from the hub of a gear I46. The gear I46 rotates loosely on a stud I48 fixed in the machine frame, the mechanism thus described comprising a direct acting train of connections between the crank I44 and the feed feet.

It is understood, in general, that the nature of any driving mechanism, not employing cams and followers or rolls for actuating devices in a machine of the type referred to, may be determined by considering separately the character of the main rotating member in the machine and the connections driven thereby. A convenient classiflcation, particularly in the case of the present invention, assigns such members to either of two groups. One of these groups includes the use of a simple constant speed rotating crank or eccentric member. The other group includes a camless rotating varying speed-ratio drive, such for instance, as that employing planetary gear action or a drag-link.

In the connections driven bythe main rotating members there also are two corresponding groups of linkages, one of the direct actin oscillating type in which the full stroke of acrank pitman or eccentric strap is employed to-provide the full stroke of the device operated thereby. The other connection group is of the compound timing-changing type in which the operated device is caused to dwell or evenhas its motion reversed at an intermediate point in the stroke of a crank pitman or eccentric strap on the rotating member or drive. To obtain timing change, the usual practice is to provide a lever and link connection in which the pivots thereof are brought into substantial alinement or are carried past a position of alinement before the end of the stroke of the crank pitman or eccentric strap is reached.

In the illustrated machine, two rotating varying speed-ratio drives are employed generally similar to that disclosed in United States Letters Patent No. 2,309,595, granted January 26, 1943 upon application of Lester E. James.

A lower one of the rotating varying speed-ratio drives rotates thefeed actuating gear I46 with its crank, a single rotation for each two rotations of the varying speed-ratio drive, in such a way that it imparts a rapid movement to the feed feet twice during each sewing cycle, once during feeding movement and once during back feeding movement thereof. Between the times of feeding movement, the movements of the feed feet and the actuating connections are relatively slow at which time formation and tightening of each stitch is being accomplished.

The lower rotating varying speed-ratio drive for the gear I45 includes a tubular variable speed shaft IE|havinga spur gear I52 secured thereto, as shown in Figs. 3 and 5, meshing with the teeth on the gear I48. The shaft I50 together with a pinion I54 thereon comprises thedriven member of the varying speed-ratio drive. For rotating the pinion I54 its teeth engage those of a gear toothed segment" I56 pivotally mounted at [58 for oscillation near the outer edge of a flanged disc I60. Except for movement of thesegment about its pivot I58 the pinion IE'A'and'shaft I 58 wouldbe rotated-in unison with the disc. However, the segment I 56 has loosely secured therein a pin I 62 forminga connection with one end of an eccentric strap I64 surrounding a stationary eccentric I56, which during rotation of the discv IBIlcauses the segment to oscillate about its pivot 8 has imparted to it a rotation of varying speedratio.

The disc ISO is rotated twice during each sewin cycleso that itimparts two relatively quick and two relatively slow movements to the pinion I54 during each sewing cycle. The gear I52 has one-half'the number of teeth as those on the gear $46 so that only a single feeding movement is imparted to the feed feet during each sewing cyole, the arrangement being such that a quick movement occurs during actual feeding movement. Another quick movement occurs during To drive the disc I60 of the lower varying speed ratio drive two revolutionsfor each single rota-,-

tion of the sewing shaft,the disc has secured to its rearward side of a spur'gear I68 having half the number of teeth as a driving gear i'iotherefor on the main sewing shaft' 84. The driving gear iron mounted for convenient removal from thesewing shaft both for purposes of assembly and accessibility to'the parts in the machine, as well as -,to enable convenient timing adjustments to be made. For these purposes, the gear has an elongated hub/and a flat collar portion at its rearward side engaging a shoulder I'i2 on the main sew'ing shaft. The hub of the gear has an opening to receive the shaft and is clamped to the shaft by a conical nut I I4 secured in clamped position by a multi-finger washer I76. In clamping the gear I70 against the collar ii? pressure is exerted upon an anti-friction bearing I'EZ- on the sewing shaft to retain it in place within an opening rec in the machine frame, the bearing forming a support for the forward end of the sewing shaft. The support for the rearward end of the sewing shaft is best shown in Fig. l and is similar to the bearing I78. The rearward su' port consists of an anti-friction bearing I82 clamped to the shaft by a nut I84 locked in place by a multi-finger washer N36. The bearing I82 also is clamped against axial movement in the machine frame between a flanged sleeve I88 rigid with the frame and a clamping ring I99 secured to the flange of the sleeve. The sleeve I88 in. turn. has an internal shoulder against which the bearing is clamped by the ring 190.

Besides operating the feed feet along the line of feed, the lower varying speed ratio drive !5Il. IfiIi also serves to rotate. the shuttle Ii twice during each sewing cycle with a. rapid rotating. motion during the time the shuttle is receiving. each loop of needle thread,-ind-icated at E9 I, and with a dwell in its movement while each needleloop is being shed from the shuttle. For thesepurposes, the. shaft IEEhas at its forward end a: bevel'gear I92 meshing with a corresponding gear i94 on the underside of the shuttle. The gear 34' and the shuttle are mounted to rotate on a vertical axis comprising a hollow vertical shaft I99 secured inthe machine frame at an angle of ninety degrees to the plane of the work operated upon and entering a suitable bearing opening within the gear F94 and the shuttle.

The shuttle is of conventional loop-taker form with a beak I93 (see Fig. 13) and an internal raceway'to receive a projecting radial flange 266' (Fig. 8) of a discoidal thread case 2&2 held from rotation with the shuttle and arranged tore-' ceive a supply of locking thread 203 withinit.

relatively to the disc; In sodoing, the pinion I54" To retain the thread-case from rotation -wit'h'- the 9 shuttle an upwardly projecting hollow arm 284 of the machine frame has at its upper end a notch 286 within which is loosely disposed a forwardly projecting lug 288 formed integrally with the thread case. As each loop of needle thread I9I is carried about the thread case by the shuttle, it is drawn upwardly into the notch 205 and eventually is carried through the space between the lug and the notch. The shuttle is held stationary while the loop is carried between the lug and the notch, thus avoiding pressure of the lug on one side of the notch and facilitating release of the loop. The thread case also has a locking thread tension 2I0 comprising a circular spring strip disposed within a circumferentl'al gro.ove in the side wall-of the thread case.

The hookneedle. 2 is clamped to the'upper end of a reciprocating needle bar 2I2 slidingly mounted in bearing sleeves 2 I4 and 2 I 6 in the machine frame (see Fig. 3), with its open hook facing against the directiomof work feed. In order to give the necessary dwells and rapid movements required while loopingthe needle and while transferring the needle loop to the shuttle the needle bar is actuated by mechanisms including one of the constant speed typegdriven by the main sewing shaft and link motion connections of the compound timing-changing type.

To provide simple and effective means for assisting in transfer of the needle loop from the needle to the shuttle, the loop picker I2 has its free loop entering end pointed in the same direction as the beak I98 of the shuttle. The loop entering end of the picker which cooperates with the needle to disengage the loop from the needle and to hold one side of the loop in the path of the shuttle beak is thus pointed against the direction of work feed, the shuttle beak being pointed similarly. The picker I2 also is actuated by compound timing-changing connections including a part of the needle actuating link motion.

The needle and picker actuating mechanism is driven from the main sewing shaft 84 through the constant speed crank 80 at the forward end of the sewing shaft just behind the forward main bearing I78, as best shown in Fig. 3.

Referring also to Figs. 6 and 7, the crank 88 is surrounded by a bearing of a pitman 2I8 having its outer end pivotally connected at 220 with the upper arm of an angle lever 222 fulcrumed loosely on a shaft 223 secured in the machine frame by a draw bolt 224. The shaft 223 forms a support about which the driving disc I68 rotates. The mid-portion of the shaft 223 also has secured it to the eccentric I66 for the feed actuating varying speed ratio drive and the forward end of the shaft 223 is reduced in diameter to provide a spindle about which the tubular shaft I58 rotates. The lower arm of the lever 222 has two forks, one of which is pivotally con- :nected at 225 with a link 226, in turn connected to the shorter rearward arm of a forked lever -22.8 including a shaft 236 to which the lever 228 is secured, rotatably mounted in the machine frame. The forward arm of the lever 228 being at the front of the machine (see Fig. 3) is connected through a link 232 with a pin 234 projecting from a block 236 clamped to the needle bar 2I2. In the needle actuating mechanism the lower armof the lever 2 22 and the link 226 have their pivots brought into substantial alinement and are carried past alinement to cause the timing in the stroke of the needle to differ from that of the pi m n 2 8 and al o t :ie ward arm 91 lever :28

7 bell crank 244 including a horizontal shaft 248,

the forward arm of which bell crank is connected througha link 248 to a pin 25!) carried by a lug on the picker !2. The picker I2 is in the form of an oscillating arm mounted on a stud 252 secured in the machine frame along the line of the Scam inserted by the stitch forming devices beyond the needle.

A feature of'the illustrated machine contributing effectively to smooth accurate operation at relatively high speed comprises the arrangement of the awl and needle looper. The awl 4 is somewhat longer than required for the thickness of work intended to be operated upon by the machine and is secured to the lower end of a reciprocating bar 254 within spaced bearing sleeves 258 (see Fig. 3) secured in an overhanging portion of the machine frame and in vertical alinement with the bearings 2 I4 and 2 I 6 for the needle bar.

To guide the awl and to prevent deflection, the lower end of the awl passes through an axial opening 251 in 'a'spindle at the side of the work Opposite the shuttle, comprising the needle looper 8 rotatably mounted in bearings 258 also in alinement with the needle and awl bar bearings, the needle also entering the axial opening during the looping operation. The opening 251 is concentric with the axis of looper rotation so that rotation of the looper spindle does not interfere with the reciprocation of the awl but does insure working engagement and penetration by the awl with certainty at the desired location.

i The awl actuating mechanism is driven from the main sewing shaft 84 through an upper rotating varying speed ratio drive connected through a compound timing-changing linkage.

The upper varying speed ratio drive for the awl mechanism consists of a flanged disc 260 (see Figs. 3, 6 and '1) having gear teeth meshing with the driving gear I18 on the main sewing shaft I 84 and in turn rotatably mounted on the midfor rotation therein a pivot 266 to which is secured a gear toothed segment 268 arranged for oscillation with the pivot. The teeth of the segment 268 mesh with those of a pinion 218 rotatable on the reduced forward end of the shaft 262. The hub of the pinion projects through an opening formed in a vertical removable partition 212 in the frame of the machine, the partition holding the pinion against displacement from the shaft 262. To the hub of the pinion 218 at the forwardside of the partition 212 is secured a crank arm 214 having a crank pin 216 to impart a varying speed, drive for the link connections. The segment 268 is oscillated about the axis of its pivot 286 by a pin 218 (see Fig. 7) on the segment, forming a connection with one end of a strap 28!] surrounding a stationary eccentric 282. The eccentric 282 is secured to the shaft 262 which projects through the flanged disc 260 of the varying speed ratio drive.

clamped to the awl bar 254.

for the awlactua-ting mechanism comprise-a pitman 28 surrounding at one end the crank pin 2E6 andat the other end a pin 286 on an axially elongated bell crank 28%. The bell crank 288 has asleeve portionrotatably mounted on a fixed pin 290 secured at its ends in a lug on the partition 2'i2 and in a forwardly disposed web of the machine frame, respectively. The forward arm of the bell crank 288 carries a pivot joint beyond the pitman 284 comprising an integral pin 292 surrounded by one end of a link 294 connected in turn by a pin 296 projecting from a block 298 The forward arm of the bell crank 288 and the link 294 have their pivot joint brought into substantial alinement with the pins 255 and 296 as illustrated in Fig. 7 to cause the motion of the awl to be reversed slightly during continued movement of the pitman 284 in one direction and to cause a more rapid penetrating and retracting movement of the and than would be produced otherwise by the pitman. The effect of the reversal is. slight in this instance, however, causing, in effect, a dwell inthe movement of the awl while disengaged from the work.

ihe needle looper B- is actuated by a mecha nism best shown in Figs. 3 and 19 to 22, inclusive. Thi mechanism comprises gear teeth 300 on the looper spindle, engaged by teeth on a gear segment forming a part of a lever 302 fulcrumed on a vertical pin 3% secured at its upper and lower ends in the frameof the machine. A rear wardly extending arm of the lever 302 is forked and has secured between the forked portions a pin 3H5, provided with a. central spherical enlargement. Surrounding the enlargement of the pin 306 is a correspondingly shaped socket at one end of a link 368 having at its other end a corresponding socket surrounding the spherical head of a pin 313. The pin 31-0 is secured in a crank arm are fastened to the forward end of a rockshaft 3M- rotatable ina bearing portion 316 of the machine frame (see Fig. 4-). At its rearward end, the. rockshaft 35: is connected to an arm 3|8 connected in turn by a link 320 with one end of an arm 322 rotatable on a pin 324 secured in a lug on the machine frame by a drawbolt 326. Between the ends of the arm 322 is a laterally projecting lug carrying a pivot 328 connected to a pitman 333. The pitman 330 surrounds the crank on the main sewing shaft 84.

Cooperating with the rotary needle looper in a novel manner, particularly advantageous in handling the needle thread accurately and at high sewing speeds, the thread measuring finger ii! is arranged to rotate on a horizontal axis dis posed at an angle of 90 to the vertical rotary axis of the looper 8. To prevent the thread finger Hi from interfering with the needle, the finger is in the form of a disc member having along one portion of its edge an arcuate flange 332 (see Figs. 8 et seq.) which projects into the path of the thread carried by the looper at one side of the needle between the looper and the last formed stitch in the work. At one end of the flange 332 there is a thread receiving notch 3'33 and the flange tapers toward its other end, finally merging with the disc portion of the looper.

To insure accurate measurement of the needle thread 19! by the thread finger I0 and to trap and prevent displacement of the measured supply of thread until released, the flange 332 moves within a concavity out within the stationary guide foot it, the surface of the concavity being disposed in close proximity to the thread finger.

12 Byreason-of its closeproximit-y the thread measuring. finger moves along the surface so the thread'ispressed against the concave surface of the guide foot. To. trap the measured thread betweenthe flange 33,2 and the guide foot so that thereis no possibility, of escape for the thread, the concave surface in the guide foot has along its=edgea circular groove 334 providing clearance for the thread'between; the surface and the thread finger when the thread finger is/in its thread measuringposition, the groove being indicated Figs. 10, 11 and 12 only.

The needle thread. as. it enters the machine passes through. the tensionandjlock 16 over the take-up 14 through a. guiding slot in the machine frame (see Figs 1 and 2) end t hrcugh an eccentric thread g uiding opening in an enlargement on the looper spindle. ,The operation of the looper and thread measuring finger will be apparent from the illustrations of Figs. 8 to 1d, inclusive, in whichFig 8 shows the eccentric thread guiding opening 335 of the looper at the side of the looper axis of rotation with the previo I y formed stitch in the work. When the awl has penetrated the work, as in Fig. the looper starts. its rotation, in the direction of the arrow in that figure in order to carry the thread guiding opening 338, to a position at one side of the-needle and. behind the axis of looper rotation and into, the path of the flange 332 on ,the thread finger. When the opening 338 in the looper reaches a position at one side and behind the axis. of looper rotation, the thread finger is. actuated-in the direction of work feed during oscillation'in the. direction of the arrow 339 in Fig. 10. to engage the needle thread it! and to start a measurement thereof. During continued measuring movement. of the thread finger rotation of the looper is reversed. The thread finger is actuated finally to the position of Fig. 11 and during. reverse rotation of the looper in the direction of" the arrow in that figure the thread is laid in the hook of the. needle, the needle enter ing the awl guiding opening, in the looper. As soon as the. thread is laid in the hook of the needle the. needle retracts, as shown in Fig. 12. and the thread finger is actuated in the opposite direction to release thread to, the retracting needle. At the lower endof the needle stroke the thread finger isv entirely disengaged from the thread and moves to, the position shown in Fig. 13 where it remains until the stitch is completed and is being drawn from the. shuttle. During these movements of the thread the work is fed a stitch length, as indicated by the arrow in preparation for the insertion of anew stitch. 1e illustrates the positions of the parts just before the thread is disengaged from the thread case and thread case retainer lug 26.3. At this time in the sewing cycle, the thread finger starts again to move toward the needle thread.

The operation of the loop picker in transferring the thread from the needle to the shuttle is clearly shown in Fig. 13, the loop of needle thread being completely disengaged from the needle before engagement with the shuttle and the open hook of the needle facing against the direction of work feed. To assist in this operation, the loop picker is pointed at its free end in the same direction as the loop taker beak and the feed of the work and is formed with a central opening within which the needle enters during transfer of the needle loop in a manner similar to that in the machine of United States Letters Patent No. 2,431,404 granted November 25, 1947 upon application of the present inventor.

The thread finger is actuated through a mechanism driven from the crank 89 on the main sewing shaft (see Figs. 3,. 17 and 18); For this purpose, the crank 88 has surrounding it a pitman ace connected by a pivot 342 supported at its ends by the sides of a bifurcated lever 344 fulcrumed on a shaft 345 in the frame of the machine. The lever 344' has one of its arms pivotally connected to a link 348, in turn connected to an arm 353 secured to a'horizontal shaft 352 rotatable in the machine frame. 'At the forward end of the shaft 352 is a forked arm 354 pivotally connected to a link 355 which in turn is pivotally connected to an arm 350 secured to a shaft 360 rotatable in stationary bearings.

The shaft 360 carries a gear segment 362', the

teeth o f 'which mesh with corresponding teeth on an incomplete pinion 334 fast to a thread finger shaft 358 rotatabl along its central portion in a fixed bearing 358 (see Fig. 3) secured to the machine frame and at its rearward end in a bearing lug on the partition 213. The disc of the thread finger I8 is formed-integrally with the shaft 833 and comprises an enlarged head on the shaft. It will be noted with reference to Figs. 17 and 18 that the uppermost arm "of the lever 344 and the link 343 form a toggle which is moved past a position of alinement of its "centers and the arm 354 and the link 356 form asecond toggle both of which approach positions of alinement during operation of the machine giving an increased dwell in the motion of the thread finger and changing the timing of the thread finger to this extent from the oscillatory motion i1n-- parted by the crank 80 to the pitman 340.

The take-up I4 is illustrated in Figs. 3, 15 and 16 and comprises a forwardly curved arm formed integrally with a horizontal shaft 310 rotatable in the machine frame in the upper part thereof. The take-up arm is located at the front end of the shaft 310 and at its rearward end the shaft has secured to it a second arm 312 (see Fig. 4) provided at its outer end with an internally threaded portion. The threaded portion of the arm 312 receives within it a threaded shank of a forked block 374 having extending across its forked portion a pivot 313. The pivot 310 is surrounded by the upper end of a link 318 within the fork of the block 314 (see Fig. 4) the lower end of which link surrounds a pin 380 secured between the sides of a fork armed lever 382 mounted for oscillation on a fixed shaft 384. The lever 382 also is connected through its opposite arm to a link 3%, in turn connected to a pin 388 on the outer end of a pitman 390 surrounding the crank 82. To modify the motion of the pitman 399 it is pivotally connected along its mid-portion with a radius arm 392 in turn rotatably mounted on a pin 394 secured in a lug on the frame of the machine by a clamp bolt 395, best shown in Fig. 4. The outer end portion of the pitman 390 and the arm 392 form a compound toggle with the link 385 to provide a substantial timing-changing action with reference to the rotary movement of the crank 82, providing a desirable movement in the take-up l4.

The combined thread tension and lock is operated during each sewing cycle to increase and decrease the tension on the thread so that the thread may be handled properly by the stitch forming devices during stitch formation and so that each stitch may be set tightly and at a uni form depth within the substance of the work after stitch formation. The thread tension and lock consists of a pair of perforated discs 399 14 (see Figs. 1, 2, 3, and 23) between "which the thread passes and through which extends a lengthwise sliding lock actuating shaft 398 passing horizontally through an opening into the machine frame. The rearmost disc 396 is pressed against the machine frame and the forward disc is pressed against the thread bya spring 499 coiled about the shaft 398. The spring 400 acts between the outer disc and a thumb nut 402 threaded on the outer end of the shaft. At the rearward end of the shaft 398 it is surrounded by a coil spring 404 (Fig. 3) stronger than the spring 400 at the forward end of the shaft. When allowed to expand, the spring 404 compresses the spring 400 and locks the thread with a heavy pressure. The rearward end of the shaft is threaded and carries a pairof check nuts 406 acting tohold the spring 404 under compression. To actuate the thread tension and lock shaft 398 its extreme rearward end is connected to mechanism best shown in Figs. 3, 23 and 24. The rearward end of the lock shaft is threaded into a transverse pin 408 and is held from rotation in the pin by a check nut M0. The pin 408 is rotatable in a forked lever 3 I2 fulcrumed on a stud 4I4 secured in the machine frame. A horizontal rearwardly extending arm of the lever 2 has a lengthwise passage at the end of which is a socket to receive the upper ball headed end of a link 4l8 held in place by a spring 4I8 within the passage of the lever arm, the spring being compressed between the fulcrum pin 4M and the ball head of the link M6. The lower end of the link M6 is pivotally'connected by a pin 429 to a generally H-shaped cam. arm 422 fulcrumed in turn on an adjusting lever 424.

The mechanism for actuating the thread tension and lock comprises a roll 426 at the rearward end of the pin 420 engaging an open cam 428 on. the main sewing shaft. The cam 428 consists of a disc disposed between the cranks and 82 providing a reinforcement and a strengthening member for the main sewing shaft between the cranks. The cam 428 rotates in the direction the arrow on the cam shown in Figs. 3 and 23, the resistance caused by friction between the cam and the roll 428 tending to move the roll in the same direction when the cam arm is free to swing. The thread tension and lock mechanism is adjustable to change the timing of lock' actuation with relation to the rotation of the cam. on the sewing shaft. For this purpose, the cam arm 42-2 of the thread tension and lock actuating mechanism is arranged for swinging movement with the adjusting lever 42 4. The adjusting lever 424 is offset and provided with an elongated hub. At the forward end of the hub of lever 42% is a forked downwardly extending arm having a pivot 430 secured therein on which the cam arm 422 is pivotally mounted. An upwardly extending arm of the adjusting lever 424 has formed thereon an integral pin portion surrounded by an eye at enlarged end of an adjusting link 432. The adjusting link passes through an opening in the thus ofiered by the cam r011 tends to hold the adiustinglink and lever at the limits of their adjusting movement.- To accelerate the time of operation of the thread lock, the thumb nut is loosened and. the adjusting lever is freed for swinging movement with the cam arm 422 in the same direction as the cam movement and the link 432 is surrounded by a coil spring 436 acting between. the enlarged eye end of the link and the inner surface of the machine frame. If there is for any reason an unusual resistance offered to relative movement between the cam 428 and the roll 426, this resistance will not effect the adjustment or tend to compress the spring 436, the spring acting to move the adjust ing lever always in the direction of cam movement and not against it. To limit free movement of the adjusting lever by the spring 436, a downward projection therefrom is notched to receive a fixed pin 431 (see Fig. 3) secured in the frame of the machine.

The operation of the machine will be more clearly understood with reference to Fig. of the drawings. As indicated therein, the and acts to penetrate the work during the first part of each sewing cycle. This occurs while the work is clamped between the stationary guide foot and the work support, the relative position of the work being shown by the shaded area. The needle is then projected upwardly through the aWl perforation in closed spaced relation to the awl as it withdraws, so that no chance of work displacement occurs during the transfer of the needle to the awl perforation. The take-up takes up the thread at a time when the work is clamped between the upper and lower feed feet. Each stitch actually is set after the feed takes place and the work is clamped by the guide foot and work support, the awl starting to enter the work at about the same time. In this way, there is no opportunity for gripping the thread between the work and the work support while the take-up is contracting each loop of thread from its state of maximum extension substantially to the surface of the work, with the result that a uniformly reliable loop contraction is provided.

The thread is controlled with certainty during formation of each stitch by the thread lock which is closed, particularly while the take-up is giving up thread to the shuttle. The thread lock is released after each needle loop is drawn to the surface of the work before each stitch is set, providing only an effective tension while the take-up is drawing an amount of thread from the supply determined by the thickness of the work. The thread lock is closed after the thread is drawn from the supply. As soon as the thread lock comes on, gripping the thread, the needle loop with looking thread is drawn a uniform distance into the work to set the stitch. Regulation of the time at which the thread lock comes on is adjustable through the time range indicated by the solid and dot-dash lines and the rotation Off-On of the thread lock curve in Fig. 25. This lock application time occurs nearly at the final end of the taking up stroke of the take-up.

For controlling the running of the machine the main sewing shaft carries a driving and stopping mechanism including a slidable clutch member 438 splined on the shaft and having secured to its hub a bearing 440 engaged by a pair of diametrically opposed pins 442 in a yoke 444. The yoke 444 comprises a lever fulcrumed on a fixed rod 446 and has a horizontal arm carrying a pin 448. The pin 448 is engaged by the lower end of a tension spring 450, the upper end of which is hooked over a stud 452 threaded into the machine frame. The spring 456 causes the clutch member 438 to be drawn into frictional engagement with a circular brake disc 454 secured within a recess of the frame surrounding the shaft 84. When the clutch member is drawn against the disc a braking action is effected causing the main sewing shaft to be brought promptly to rest.

To actuate the clutch member 438 away from the brake disc 454 and to cause the sewing shaft to be rotated, the pin 448 has connected to it a treadly rod 456 extending downwardly to a conveniently located treadle (not shown) at the base of the machine. Depression of the treadle rod moves the clutch member 438 away from the disc 454 and into engagement a rotating driving clutch member 458 loosely mountedonthe end of the shaft and havin (secured to its hub 'a'friction reducing beari 4 60 disposed between the hub of the driving member and a cover plate 462 enclosing the recess containing the disc 454 in the fran ieof the machine. The bearing 460 thus assists in supporting the'outer end of the main sewing shaft. To rotate the driving clutch member 458 its hub has secured to it a pulley 464 driven by a belt-extending to a suitable source of power (also'not shown). The extreme outer end of the shaft has pinned to it a hand wheel 486 for bringing the sewing shaft to a convenient stopping position if required.

To assist in releasing and replacing the work in the machine, the work support is connected to a second foot treadle, not shown, which when depressed lowers the work support from the guide foot I3. To this end the rearward end of the shaft 42 has pinned to it a horizontal arm 468 (see Fig. 4). Pivotally connected to the arm is a downwardly extending treadle rod 410 connecting the arm with the work support lowering treadle.

For convenience in removing a locking thread supply bobbin from the thread case 202, the hollow shaft I96 has slidingly mounted within it a vertical pin 412, the upper end of which is guided in alinement with an opening in the bottom of the thread case (see Figs. 1, 2 and 3). The lower end of the pin has an enlarged perforated head for receiving a pin 414 passing through an H- shaped link 416. The link 416 also carries a pin 418 forming a pivotal connection with a finger lever 48!! fulcrumed in the machine frame and projecting through the right side thereof. Downward movement of the projecting arm of the finger lever 486 raises the pin 412 and ejects the locking thread supply bobbin. To hold the ejector pin 412 in lowered inoperative position, the pin 418 has stretched between it and a fixed stud 482 a tension spring 484.

The nature and scope of the invention having been indicated and a specific embodiment having been described what is claimed is:

1. A sewing machine having a needle, a guide foot, a work support and a vertical guideway along which the work support is movable toward and from the guide foot, in combination with a pair of feed feet at opposite sides of a location ordinarily occupied by the work, and means for actuating the feed feet to clamp and feed the work, one of said feet being connected to the work support by a floating actuating lever to cause the work support to be lowered from engagement with the work during feeding movement of the feed feet.

2. A sewing machine having a needle, a guide foot, a work support and a vertical guideway along which the work support is movable toward and from the guide foot, in combination with a feed foot connected to the work support by a floating actuating lever to cause the work support to be lowered from engagement with the work during feeding movement of the feed foot and mechanism for actuating the feedfoot for causing the feed foot to clamp the work comprising a vertically sliding connection with the floating lever. V

3. A sewing machine having a needle, a guide foot, a work support and a vertical guideway along which the work support is movable toward and from the guide foot, in combination with a pair of feed feet at opposite sides of a location ordi- "na'rily'bccupiedby the work, means for actuating the feed feet to clamp and feed the work, one of said feet being connected to the work support by a floating actuating leverto cause the work support to be lowered from engagement with the work during feeding movement of the feed feet and mechanisms for actuating feed feet in the direction of feed comprising a rotating varying speed-ratio drive.

4. A sewing machine having a needle, a guide foot, a work support and a vertical guideway along which the work support is movable toward and from the guide foot, in combination with a pair of feed feet at opposite sides of a location normally occupied b the work, both of which are actuated to clamp and feed the work, connections including a floating lever betweenthe work support and one of said feed feet to cause the work support to be lowered from engagement with the work during feeding movement of the feed feet, and mechanisms for actuating the feed feet in the direction of feed comprising a rotating varying speed-ratio drive and a single vertical lever connecting the two feed feet.

5. A sewing machine having a needle, a guide foot, a work support and a vertical guideway along which the work support is movable toward and from the guide foot, in combination with a pair of feed feet at opposite sides of a location normally occupied by the work, both of which are' actuated to clamp and feed the work, connections including a floating lever between the work support and one of said feed feet to cause the work support to be lowered from engagement with the work during feeding movement of the feed feet, and mechanisms for actuating the feed feet in the direction of feed comprising a rotating varying speed-ratio drive, a single vertical lever connecting the two feed feet and a motion reversing connection between the end of the connecting lever and one of the feed feet to cause both feet to move along the line of feed in the same direc tion.

6. 'A sewing machine having a needle, a guide foot, a work support and a verticalguideway along which the work support is movable toward and from the guide foot, in combination with a pair of feed feet at opposite sides of a location normally occupied by the work, both of which are actuated to clamp and feed the work connections including a floating lever between the work support and one of said feed feet to cause the work support to 'be lowered from engagement with the work during feeding movement of the feed feet,

A and mechanisms for actuating the feed feet in therdirection of .feed comprising a rotating varying speedratio drive, a single vertical lever connecting. the two feed feetfand an adjustable throw connection for actuating the connecting lever.

'7. A sewing machine having a hook needle, an awl, and other stitch forming devices, a main sewing shaft for actuating the stitch forming devices, in combination with link motions connected to the needle and awl, each motion including a crank and pitman driven from the main sewing shaft and the awl link motion being driven through a camless varying speed-ratio device connected between the awl link motion and the main sewing shaft.

8. A sewing machine having a hook needle, an awl, and other stitch forming devices, a main sewing shaft for actuating the stitch forming devices, in combination with a compound timechanging linkage for actuating the needle from the main sewing shaft, a camless rotating varying speed-ratio device driven by the main shaft, and a compound timing-changing linkage driven by said device for actuating the awl.

9. A sewing machine having a hook needle, an awl, and other stitch forming devices, a main sewing shaft for actuating the stitch forming devices, in combination with a link motion for actuating the needle from the main sewing shaft and a loop picker actuated by the needle actuating link motion to engage each loop carried by the needle.

10. A sewing machine having a sewing shaft, a hook needle, a needle looper, a guide foot, and a work support, in combination with a feed foot connected to the work support, and mechanism for actuating the feed foot in the direction of feed comprising a member rotating twice for each single rotation of the sewing shaft, and a rotating varying speed-ratio drive on said member and a member driven a single rotation for each two rotations of the varying speed-ratio drive connected between said drive and the feed foot to cause quick feeding and back-feeding movements with relatively slow movements between the quick movements thereof.

11. A sewing machine having a sewing shaft, a hook needle, a needle looper, a guide foot, and a work support, in combination with a feed foot connected to the work support, mechanism for actuating the feed foot in the direction of feed comprising a member rotating twice for each single rotation of the sewing shaft, and a rotating varying speed-ratio drive on said member and a member driven a single rotation for each two rotations of the varying speed-ratio drive connected between said drive and the feed foot to cause quick feeding and back-feeding movements with relatively slow movements between the quick movements thereof, and mechanism driven from the sewing shaft for actuating, the feed foot to clamp and release the work.

12. A sewing machine having a sewing shaft, a hook needle, a needle looper, a guide foot, and a work support, in combination with a feed foot connected to the work support, mechanism for actuating the feed foot in the direction of feed comprising a member rotating twice for each single rotation of the sewing shaft, and a rotating varying speed-ratio drive on said member anda member driven a single rotation for each two rotations of the varying speed-ratio drive connected between said drive and the feed foot to cause quick feeding and back-feeding movements with relatively slow movements'between the quick movements thereof, and a second feed foot at the opposite side of the work from the first-mentioned feed foot acting in unison therewith to clamp and feed the work.

v 13. A sewing machine having a sewing shaft, a hookneedle, a needle looper, a guide foot, and 

